Customized patient-specific orthopaedic surgical instrument and method for preparing a patient&#39;s femur

ABSTRACT

An orthopaedic surgical instrument includes a customized patient-specific 5-in-1 cutting block having a plurality of ribs and cutting guide slots extending between each rib. A bone-facing surface of each rib has a customized patient-specific negative contour configured to receive a portion of a corresponding positive contour of the patient&#39;s femur.

TECHNICAL FIELD

The present disclosure relates generally to orthopaedic surgicalinstruments and, more particularly, to customized patient-specificorthopaedic surgical instruments.

BACKGROUND

Joint arthroplasty is a well-known surgical procedure by which adiseased and/or damaged natural joint is replaced by a prosthetic joint.For example, in a total knee arthroplasty surgical procedure, apatient's natural knee joint is partially or totally replaced by aprosthetic knee joint or knee prosthesis. A typical knee prosthesisincludes a tibial tray, a femoral component, and a polymer insert orbearing positioned between the tibial tray and the femoral component. Ina hip replacement surgical procedure, a patient's natural acetabulum isreplaced by a prosthetic cup and a patient's natural femoral head ispartially or totally replaced by a prosthetic stem and femoral ball.

To facilitate the replacement of the natural joint with a prosthesis,orthopaedic surgeons use a variety of orthopaedic surgical instrumentssuch as, for example, cutting blocks, drill guides, milling guides, andother surgical instruments. Typically, the orthopaedic surgicalinstruments are reusable and generic with respect to the patient suchthat the same orthopaedic surgical instrument may be used on a number ofdifferent patients during similar orthopaedic surgical procedures.

The orthopaedic surgical instruments may also be customized to aspecific patient. Such “customized patient-specific orthopaedic surgicalinstruments” are single-use surgical tools for use by a surgeon inperforming an orthopaedic surgical procedure that is intended, andconfigured, for use on a particular patient. It should be appreciatedthat these instruments are distinct from standard, non-patient specificorthopaedic surgical instruments that are intended for use on a varietyof different patients. These customized patient-specific orthopaedicsurgical instruments are distinct from orthopaedic prostheses, whetherpatient-specific or generic, which are surgically implanted in the bodyof the patient. Rather, customized patient-specific orthopaedic surgicalinstruments are used by an orthopaedic surgeon to assist in theimplantation of orthopaedic prostheses.

SUMMARY

According to one aspect of the disclosure, an orthopaedic surgicalinstrument includes a customized patient-specific 5-in-1 cutting blockhaving a keel including a distal segment extending from an anterior endto a posterior end. An anterior segment extends proximally from theanterior end of the distal segment. A posterior segment extendsproximally from the posterior end of the distal segment. A plurality ofribs extends medially and laterally from the distal segment, anteriorsegment, and the proximal segment of the keel. Each rib includes a firstend coupled to the keel, a cantilevered second end, and a bone-facingsurface extending from the first end to the second end of each rib. Eachbone-facing surface of each rib has a customized patient-specificnegative contour configured to receive a portion of a correspondingpositive contour of the patient's femur. The plurality of ribs cooperateto define a plurality of cutting guides. Each cutting guide includes aslot having an open outer end defined between corresponding cantileveredsecond ends of adjacent ribs.

In some embodiments, the cutting guides may include a first chamfercutting guide and a second chamfer cutting guide. Each of the firstchamfer cutting guide and the second chamfer cutting guide may includemedial and lateral slots. The first chamfer cutting guide may include afirst slot aligned with a second slot. The second chamfer cutting guidemay include a third slot aligned with a fourth slot.

In some embodiments, the cutting guides may include a distal cuttingguide having medial and lateral slots. The distal cutting guide mayinclude a first slot aligned with a second slot.

In some embodiments, the cutting guides may include an anterior cuttingguide and a posterior cutting guide. Each of the anterior cutting guideand the posterior cutting guide may have medial and lateral slots.

In some embodiments, the keel may include a customized patient-specificnegative contour configured to receive a portion of a correspondingpositive contour of a surface defining the patient's intercondylarnotch.

In some embodiments, an anterior bore may extend through the anteriorsegment. A distal bore may extend through the distal segment. Theanterior bore and the distal bore may each be configured to receive abone fixation pin to couple the cutting block to a distal end of thepatient's femur.

According to another aspect of the disclosure, an orthopaedic surgicalinstrument includes a customized patient-specific 5-in-1 cutting blockhaving an anterior flange including a bone-facing surface having acustomized patient-specific negative contour configured to receive aportion of a corresponding positive contour of a patient's femur. Aposterior flange includes a pair of bone-facing surfaces. Each bonefacing surface of the posterior flange has a customized patient-specificnegative contour configured to receive a portion of a correspondingpositive contour of a patient's femoral condyle. A plurality of ribs ispositioned between the anterior flange and the posterior flange. Eachrib includes at least one bone-facing surface having a customizedpatient-specific negative contour configured to receive a portion of acorresponding positive contour of a patient's femur. A pair of beamsconnects adjacent ribs of the plurality of ribs. Each beam includes abone-facing surface having a customized patient-specific negativecontour configured to receive a portion of a corresponding positivecontour of a patient's femur. The plurality of beams, the plurality ofribs, the anterior flange, and the posterior flange cooperate to definea plurality of captured cutting guides. Each captured cutting guide hasa slot that extends from a first beam of each pair of beams to a secondbeam of each pair of beams.

In some embodiments, the cutting guides may include a first chamfercutting guide and a second chamfer cutting guide. The first chamfercutting guide may include a first slot aligned with a second slot. Thesecond chamfer cutting guide may include a third slot aligned with afourth slot.

In some embodiments, the cutting guides may include a distal cuttingguide having a first slot aligned with a second slot.

In some embodiments, the cutting guides include an anterior cuttingguide and a posterior cutting guide.

In some embodiments, an anterior bore may extend through the anteriorflange. A distal bore may extend through one of the plurality of ribs.The anterior bore and the distal bore may each be configured to receivea fixation pin to couple the cutting block to a distal end of thepatient's femur.

According to yet another aspect of the disclosure, an orthopaedicsurgical instrument includes a customized patient-specific 5-in-1cutting block having an anterior flange including a bone-facing surfacehaving a customized patient-specific negative contour configured toreceive a portion of a corresponding positive contour of a patient'sfemur. A keel includes a distal segment extending from the anteriorflange to a posterior end and a posterior segment extending proximallyfrom the posterior end of the distal segment. A plurality of ribsextends medially and laterally from the distal segment, and the proximalsegment of the keel. Each rib includes a first end coupled to the keel,a cantilevered second end, and a bone-facing surface extending from thefirst end to the second end of each rib. Each bone-facing surface ofeach rib has a customized patient-specific negative contour configuredto receive a portion of a corresponding positive contour of thepatient's femoral condyle. The plurality of ribs cooperate to define aplurality of cutting guides. Each cutting guide includes a slot havingan open outer end defined between corresponding cantilevered second endsof adjacent ribs. A plurality of captured cutting guides extends throughthe anterior flange.

In some embodiments, the keel may include a customized patient-specificnegative contour configured to receive a portion of a correspondingpositive contour of a surface defining the patient's intercondylarnotch.

In some embodiments, the cutting guides include a first chamfer cuttingguide and a second chamfer cutting guide. The first chamfer cuttingguide may include a first slot aligned with a second slot. The secondchamfer cutting guide may include a third slot aligned with a fourthslot.

In some embodiments, the cutting guides may include a distal cuttingguide, an anterior cutting guide, and a posterior cutting guide.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description particularly refers to the following figures,in which:

FIG. 1 is a front perspective view of an embodiment of a customizedpatient-specific orthopaedic instrument including five cutting guidesfor cutting a patient's femur;

FIG. 2 is another front perspective view of the instrument shown in FIG.1;

FIG. 3 is a rear perspective view of the instrument shown in FIG. 1;

FIG. 4 is another rear perspective view of the instrument shown in FIG.1;

FIG. 5 is a cross-sectional elevation view taken along line 5-5 in FIG.1;

FIG. 6 is a perspective view of the instrument shown in FIG. 1positioned on a distal end of a femur;

FIG. 7 is a cross-sectional view of the instrument positioned on thedistal end of the femur taken along the line 7-7 in FIG. 6;

FIG. 8 is a front perspective view of another embodiment of a customizedpatient-specific orthopaedic instrument including five cutting guidesfor cutting a patient's femur;

FIG. 9 is another front perspective view of the instrument shown in FIG.8;

FIG. 10 is a rear perspective view of the instrument shown in FIG. 8;

FIG. 11 is another rear perspective view of the instrument shown in FIG.8;

FIG. 12 is a side elevation view of the instrument shown in FIG. 8;

FIG. 13 is a perspective view of the instrument shown in FIG. 8positioned on a distal end of a femur;

FIG. 14 is a cross-sectional view of the instrument positioned on thedistal end of the femur taken along the line 14-14 in FIG. 13;

FIG. 15 is a front perspective view of yet another embodiment of acustomized patient-specific orthopaedic instrument including fivecutting guides for cutting a patient's femur;

FIG. 16 is another front perspective view of the instrument shown inFIG. 15;

FIG. 17 is a rear perspective view of the instrument shown in FIG. 15;

FIG. 18 is another rear perspective view of the instrument shown in FIG.15;

FIG. 19 is a side elevation view of the instrument shown in FIG. 15;

FIG. 20 is a cross-sectional elevation view of the instrument takenalong line 20-20 in FIG. 15;

FIG. 21 is a front perspective view of the instrument shown in FIG. 15positioned on a distal end of a femur; and

FIG. 22 is a cross-sectional view of the instrument positioned on thedistal end of the femur taken along line 22-22 in FIG. 21.

DETAILED DESCRIPTION OF THE DRAWINGS

While the concepts of the present disclosure are susceptible to variousmodifications and alternative forms, specific exemplary embodimentsthereof have been shown by way of example in the drawings and willherein be described in detail. It should be understood, however, thatthere is no intent to limit the concepts of the present disclosure tothe particular forms disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the appended claims.

References in the specification to “one embodiment”, “an embodiment”,“an example embodiment”, etc., indicate that the embodiment describedmay include a particular feature, structure, or characteristic, butevery embodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to effect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed.

Terms representing anatomical references, such as anterior, posterior,medial, lateral, superior, inferior, etcetera, may be used throughoutthe specification in reference to the orthopaedic implants or prosthesesand surgical instruments described herein as well as in reference to thepatient's natural anatomy. Such terms have well-understood meanings inboth the study of anatomy and the field of orthopaedics. Use of suchanatomical reference terms in the written description and claims isintended to be consistent with their well-understood meanings unlessnoted otherwise.

Referring to FIGS. 1-2, a customized patient-specific orthopaedicsurgical instrument 10 is shown. As used herein, the term “customizedpatient-specific orthopaedic surgical instrument” is a surgical tool foruse by a surgeon in performing an orthopaedic surgical procedure that isintended, and configured, for use on a particular patient. As such, itshould be appreciated that, as used herein, the term “customizedpatient-specific orthopaedic surgical instrument” is distinct fromstandard, non-patient specific orthopaedic surgical instruments (i.e.,“patient-universal instruments” such as patient-universal cuttingblocks) that are intended for use on a variety of different patients andwere not fabricated or customized to any particular patient.Additionally, it should be appreciated that, as used herein, the term“customized patient-specific orthopaedic surgical instrument” isdistinct from orthopaedic prostheses or implants, whetherpatient-specific or generic, which are surgically implanted in the bodyof the patient. Rather, an orthopaedic surgeon uses customizedpatient-specific orthopaedic surgical instruments to assist in theimplantation of orthopaedic prostheses. Examples of “customizedpatient-specific orthopaedic surgical instruments” include customizedpatient-specific drill/pin guides, customized patient-specific tibialcutting blocks, customized patient-specific femoral cutting blocks, andcustomized patient-specific alignment guides. As described in greaterdetail below, the instrument 10 is a 5-in-1 femoral cutting block 12configured to be coupled to the patient's femur in a uniquepre-determined location and orientation.

The femoral cutting block 12 is illustratively formed by Direct MetalLaser Sintering (DMLS), also known as Selective Laser Sintering (SLS),which is a form of additive manufacturing technology. In DMLS, thefemoral cutting block 12 is formed in a layer-by-layer fashion usinglaser sintering in which light fuses metallic powder, forming themetallic structures that define the femoral cutting block 12. It shouldbe appreciated that other forms of additive manufacturing technologysuch as, for example, optical fabrication, photo-solidification, orresin printing may be used to fabricate the femoral cutting block 12.The femoral cutting block 12 is configured to be positioned on a distalend of a patient's femur (not shown) during a joint arthroplastyprocedure, so that the surgeon can perform resections on the distal endof the femur. The femoral cutting block 12 enables the surgeon toperform five cuts on the distal end of the femur with a single femoralcutting block 12. Specifically, with the femoral cutting block 12, thesurgeon can perform a posterior resection, an anterior resection, and adistal resection, as well as, a posterior chamfer resection and ananterior chamfer resection. The surgeon performs these resections byinserting a cutting blade through various cutting guides defined in thefemoral cutting block 12 to prepare the patient's femur to receive afemoral orthopaedic prosthetic component, as described in more detailbelow.

The cutting block 12 includes a distal segment 14 having an anterior end16 and a posterior end 18. An anterior flange 20 extends from theanterior end 16, and a posterior flange 22 extends from the posteriorend 18. The cutting block 12 also has an outer surface 30 extends fromthe anterior flange 20 to the posterior flange 22. The outer surface 30is substantially smooth. As used herein, the term “substantially” shouldbe understood to refer to the normal tolerances created by manufacturingvariation and other design criteria. As such, a “substantially smoothsurface” is one that is smooth within the normal tolerances created orpermitted by manufacturing variation and other design criteria. Abone-facing surface 32 of the cutting block 12 extends from the anteriorflange 20 to the posterior flange 22 opposite from the outer surface 30.The bone-facing surface includes a customized patient-specific negativecontour 34 that is a negative of a positive contour of a distal end 40of a patient's femur 42 (see FIG. 6).

The distal segment 14 includes a plurality of ribs 50 that are coupledat each end 52 by beams 54. In the illustrative embodiment, each rib 50includes a pair of planar surfaces 56, and each beam 54 includes aplanar surface 58. The planar surfaces 56, 58 extend from the outersurface 30 to the bone-facing surface 32 to define a plurality of slots70 between their planar surfaces 56 of adjacent ribs 50 and the planarsurface 58 of the beam 54 connecting the adjacent ribs 50. As describedin greater detail below, the slots 70 cooperate to define the cuttingguides of block 12.

The posterior flange 22 of the block 12 also includes a planar surface72, and the anterior flange 20 includes a planar surface 74. Aposterior-most beam 76 couples the posterior flange 22 to an adjacentrib 50 such that a planar surface 58 of the posterior-most beam 76, theplanar surface 72 of the posterior flange 22, and the planar surface 56of the adjacent rib 50 define one of the slots 70. An anterior-most beam79 couples the anterior flange 20 to an adjacent rib 50 such that aplanar surface 58 of the anterior-most beam 78, the planar surface 74 ofthe anterior flange 20, and the planar surface 56 of the adjacent rib 50define another of the slots 70.

The cutting block 12 also includes a pin guide 80, which extends from anopening 82 formed in the outer surface 30 of the distal segment 14 to anopening 84 (see FIG. 3) in the bone-facing surface 32 of the distalsegment 14. The cutting block 12 includes another pin guide 90 thatextends from an opening 92 formed in the outer surface 30 of theanterior flange 20 to an opening 94 (see FIG. 2) in the bone-facingsurface 32 of the anterior flange 20. The pin guides 80, 90 areconfigured to receive bone fixation pins to retain the cutting block 12on the distal end 40 of the patient's femur 42.

Referring now to FIGS. 3-4, the negative contour 34 of the bone-facingsurface 32 is formed by a number of negative contours defined in theflanges 20, 22, the ribs 50, and the beams 54. Specifically, in theillustrative embodiment, the anterior flange 20 of the cutting block 12includes a negative contour 100 that forms a portion of the bone-facingsurface 32. The contour 100 has a unique set of ridges 102 anddepressions 104 that are shaped to engage a corresponding unique set ofdepressions 106 and ridges 108 of an anterior surface 110 of thepatient's femur 42 (see FIG. 7). The posterior flange 22 also includes anegative contour 120 that forms a portion of the bone-facing surface 32.The contour 120 has a unique set of ridges 122 and depressions 124 thatare shaped to engage a corresponding unique set of depressions 126 andridges 128 of a posterior surface 130 of the patient's femur 42 (seeFIG. 7). The ribs 50 of the block 12 also cooperate to define a negativecontour 140 that forms a portion of the bone-facing surface 32. Thecontour 140 has a unique set of ridges 142 and depressions 144 that areshaped to engage a corresponding unique set of depressions 146 andridges 148 of the condyles 150 of the patient's femur 42 (see FIG. 7).The beams 54 cooperate to define a negative contour 160 that forms aportion of the bone-facing surface 32. The contour 160 has a unique setof ridges 162 and depressions 164 that are shaped to engage acorresponding unique set of depressions 166 and ridges 168 of the distalend 40 of the patient's femur 42 (see FIG. 7).

The negative contour 34 formed by the contours 100, 120, 140, and 160 ispatient-specific and matches a corresponding contour (or contours) ofthe distal end 40 of the patient's femur 42. In that way, thebone-facing surface 32 enables the cutting block 12 to be positioned onthe distal end 40 of the patient's femur 42 in a unique, pre-plannedposition so that the cutting block 12 does not have to be adjusted onthe distal end 40 of the femur 42 during use. In the illustrativeembodiment, the cutting block 12 does not require augments to offset thecutting block 12 relative to the distal end 40 of the femur 42. As such,the cutting block 12 is positioned directly on the distal end 40 of thefemur 42 and secured to the femur 42. As described below, fiveresections can then be performed with a single cutting block 12 withoutrequiring any repositioning during the surgical procedure.

Referring now to FIG. 5, the cutting block 12 includes a posteriorchamfer cutting guide 184, a posterior cutting guide 204, a anteriorchamfer cutting guide 244, a distal cutting guide 194, and an anteriorcutting guide 282. To define the posterior chamfer cutting guide 184,the posterior flange 22 and a rib 180 define a slot 182 between theirplanar surfaces 72 and 56. A rib 200 and a rib 220 of the distal segment14 define a slot 222 between their planar surfaces 56. The slot 222 isaligned with the slot 182 to define the captured posterior chamfercutting guide 184. The captured posterior chamfer cutting guide 184 isconfigured to receive a cutting tool, and it defines a posterior chamferresection guide plane 226 for the cutting tool that extends through thedistal end 40 of the patient's femur 42.

A rib 190 and the rib 200 cooperate to define a slot 202 between theirplanar surfaces 56. The slot 202 defines the captured posterior cuttingguide 204, which is configured to receive a cutting tool and defines aposterior resection guide plane 206 extending through the patient'sfemur 42.

To define the anterior chamfer cutting guide 244, the block 12 includesa rib 220 and a rib 240 that define another slot 242 between theirplanar surfaces 56. Another rib 264 and the anterior flange 20 define aslot 290 between their planar surfaces 74 and 56. The slot 290 isaligned with the slot 242 to define the captured anterior chamfercutting guide 244, which is configured to receive a cutting tool toperform and defines an anterior chamfer resection guide plane 292extending through the distal end 40 of the patient's femur 42.

To define the distal cutting guide 194, the ribs 180, 190 define a slot192 between their planar surfaces 56. The ribs 240, 260, 262, and 264all cooperate to define a slot 270 between their planar surfaces 56. Theslot 270 is aligned with the slot 192 to define the captured distalcutting guide 194, which is configured to receive a cutting tool toperform a distal resection guide plane 272 extending through the distalend 40 of the patient's femur 42.

The anterior cutting guide 282 includes a slot 280 that is definedbetween their planar surfaces 56 of the ribs 240, 260, 262, and 264 theanterior cutting guide 28 is configured to receive a cutting tool anddefines an anterior resection guide plane 284 extending through thedistal end 40 of the anterior surface 110 of the patient's femur 42.

Referring now to FIG. 6, the pin guide 90 is sized to receive a pin 300that secures the cutting block 12 to the distal end 40 of the patient'sfemur 42. The pin 300 is positioned in the patient's intercondylar notch302, as illustrated in FIG. 7, and is secured to a surface 304 thatdefines the intercondylar notch 302. The pin guide 80 is sized toreceive another pin 310 that secures the anterior flange 20 to theanterior surface 110 of the patient's femur 42. Because the pins 300,310 are located in regions of the bone that are not resected duringsurgery, the pins 300, 310 may remain in place while the surgeonperforms the resections. In some embodiments, the surgeon may remove thepin 300 when making some of the cuts so that the surgeon does not haveto resect around the pin 300. In such an embodiment, the pin 310 incooperation with the bone-facing surface 32 holds the cutting block 12is place on the patient's femur 42.

Referring now to FIGS. 8-9 another customized patient-specificorthopaedic surgical instrument 350 includes a 5-in-1 cutting block 352.Similar to the femoral cutting block 12, the cutting block 352 alsoincludes a bone-facing surface 382 and an outer surface 380 that ispositioned opposite the bone-facing surface 382. The bone-facing surface382 includes a customized patient-specific contour 384 that matches andis a negative of a positive contour of a distal end 40 of a patient'sfemur 42 (see FIG. 13).

The cutting block 352 includes a keel 354 that extends along themid-line of the block 352. The keel 354 includes a distal segment 356extending between a posterior end 358 and an anterior end 360. Aposterior segment 370 of the keel 354 extends from the posterior end 358of the distal segment 356, and an anterior segment 372 of the keel 354extends from the anterior end 360 of the distal segment 356. A pluralityof medial and lateral ribs 390 extend from the keel 354 to cantileveredends 392. Each rib 390 includes a pair of planar surfaces 394 extendingfrom the outer surface 380 to the bone-facing surface 382. A pluralityof medial and lateral slots 400 are defined by the planar surfaces 394of adjacent ribs 390 and a planar surface 402 of the keel 354 thatextends between the outer surface 380 and the bone-facing surface 382.The slots 400 include open ends 404 positioned between the cantileveredends 392 of the ribs 390. As described in greater detail below, theslots 400 cooperate to define the five cutting guides of the block 352.

The block 352 also includes a pair of pin guides 420, 430 sized toreceive bone fixation pins to secure the block 352 to the patient'sfemur. In the illustrative embodiment, each of the pin guides 420, 430extends through the keel 354. As shown in FIG. 11, the pin guide 420extends from an opening 422 formed in the outer surface 380 of thedistal segment 356 to an opening 424 in the bone-facing surface 382 ofthe distal segment 356. As shown in FIG. 9, the pin guide 430 extendsfrom an opening 432 formed in the outer surface 380 of the anteriorsegment 372 to an opening 434 in the bone-facing surface 382 of theanterior segment 372.

The customized patient-specific contour 384 is formed by a number ofnegative contours 440, 460 defined in the ribs 390 and the keel 354,respectively. Each contour 440 has a unique set of ridges 442 anddepressions 444 that are shaped to engage a corresponding unique set ofdepressions 166 and ridges 168 of the distal end 40 of the patient'sfemur 42 (see FIG. 14). The contour 460 of the keel 354 has a unique setof ridges 462 and depressions 464 that are shaped to engage acorresponding unique set of depressions 166 and ridges 168 of the distalend 40 of the patient's femur 42

Referring now to FIG. 12, the various medial slots 400 of the cuttingblock 352 are shown on a medial side 470 of the cutting block 352. Itshould be noted that in the illustrative embodiment the lateral side ofthe cutting block 352 includes the same slots described herein withrespect to the medial side 470. For example, when a distal cutting slotis referenced, it should be appreciated that the lateral side of thecutting block 352 also includes a distal lateral cutting slot thatcorresponds to the distal cutting slot on the medial side 470 of thecutting block 352. In that way, the medial and lateral cutting slotscooperate to define a posterior chamfer cutting guide 506, a posteriorcutting guide 534, a distal cutting guide 514, an anterior chamfercutting guide 574, and an anterior cutting guide 602 of the block 352.

To define the posterior chamfer cutting guide 506, the cutting block 352includes a rib 500 and a rib 502 that define a slot 504 between theirplanar surfaces 394. Another rib 530 and a rib 550 define another slot552 between their planar surfaces 394. The slot 552 is aligned with theslot 504 to define the medial side of the posterior chamfer cuttingguide 506, which is configured to receive a cutting tool and defines aposterior chamfer resection guide plane 556 extending through the distalend 40 of the patient's femur 42. As described above, another pair ofslots on the lateral side of the block 352 cooperate to define thelateral side of the posterior chamfer cutting guide 506.

The rib 530 and another rib 510 cooperate to define a slot 532 betweentheir planar surfaces 394. The slot 532 defines the medial side of theopen posterior cutting guide 534. As described above, another pair ofslots on the lateral side of the block 352 cooperate to define thelateral side of the posterior cutting guide 534. The posterior cuttingguide 534 is configured to receive a cutting tool and defines aposterior resection guide plane 536 extending through the patient'sfemur 42.

The rib 502 of the cutting block 12 and the rib 510 define a slot 512between their planar surfaces 394. The cutting block 12 also includesribs 570, 580, 582, and 584, which cooperate to define a slot 590between their planar surfaces 394. The slot 590 is aligned with the slot512 to define the medial side of the distal cutting guide 514. Asdescribed above, another pair of slots on the lateral side of the block352 cooperate to define the lateral side of the distal cutting guide514. The distal cutting guide 514 is configured to receive a cuttingtool and defines a distal resection guide plane 592 extending throughthe distal end 40 of the patient's femur 42.

The ribs 550, 570 define another slot 572 between their planar surfaces394. The rib 584 and a rib 610 define a slot 612 between their planarsurfaces 394. The slot 612 is aligned with the slot 572 to define themedial side of the anterior chamfer cutting guide 574. As describedabove, another pair of slots on the lateral side of the block 352cooperate to define the lateral side of the anterior chamfer cuttingguide 574. The anterior chamfer cutting guide 574 is configured toreceive a cutting tool and defines an anterior chamfer resection guideplane 614 extending through the distal end 40 of the patient's femur 42.

The ribs 570, 580, 582, and 584 also cooperate to define a slot 600between their planar surfaces 394. The slot 600 defines a medial side ofthe open anterior cutting guide 602 that is configured to receive acutting tool and defines an anterior resection guide plane 604 extendingthrough the patient's femur 42.

Referring now to FIG. 13, the pin guide 420 receives a bone fixation pin620 that secures the cutting block 352 to the distal end 40 of thepatient's femur 42. The pin 620 is positioned in the patient'sintercondylar notch 302, as illustrated in FIG. 14, and is secured to asurface 304 that defines the intercondylar notch 302. The other pinguide 430 is configured to receive a fixation pin 622 that secures theanterior segment 372 to the anterior surface 110 of the patient's femur42. The surgeon can resect around the pins 620, 622 because the pinsengage portions of the bone that are not resected during a surgicalprocedure. In some embodiments, the surgeon may remove the pin 620 whenmaking some of the cuts so that the surgeon does not have to resectaround the pin 620. In such an embodiment, the pin 622 in cooperationwith the bone-facing surface 382 holds the cutting block 352 in place onthe patient's femur 42.

Referring now to FIGS. 15-16, another customized patient-specificorthopaedic surgical instrument 650 includes a 5-in-1 cutting block 652.Similar to the other cutting blocks 12 and 352, the cutting block 562includes a bone-facing surface 672 and an outer surface 670 that ispositioned opposite the bone-facing surface 672. The bone-facing surface672 includes a customized-patient specific negative contour 674 thatmatches and is a negative of a positive contour of a distal end 40 of apatient's femur 42 (see FIG. 21).

The cutting block 652 includes an anterior flange 654 and a keel 656extending away from the anterior flange 654. The keel 656 includes adistal segment 658 extending from the anterior flange 654 to a posteriorend 660. The keel 656 also includes a posterior segment 662 extendingfrom the posterior end 660 of the distal segment 658. The cutting block562 also includes a pin guide 680 that extends from an opening 682formed in the outer surface 670 of the distal segment 658 to an opening684 (see FIG. 17) in the bone-facing surface 672 of the distal segment658. Another pin guide 690 extends from an opening 692 formed in theouter surface 670 of the anterior flange 654 to an opening 694 (see FIG.16) in the bone-facing surface 672 of the anterior flange 654. The pinguides 680, 690 are configured to receive bone fixation pins to retainthe cutting block 652 on the distal end 40 of the patient's femur 42.

The anterior flange 654 includes a plurality of flange ribs 700 that arecoupled at each end 702 by beams 704. Each rib 700 includes a pair ofplanar surfaces 706, and each beam 704 includes a planar surface 708.The planar surfaces 706, 708 extend from the outer surface 670 to thebone-facing surface 672. A plurality of slots 710 are defined betweentheir planar surfaces 706 of adjacent ribs 700 and the planar surface708 of the beam 704 connecting the adjacent ribs 700.

A plurality of medial and lateral ribs 720 extend from the keel 656 tocantilevered ends 722. Each rib 720 includes a pair of planar surfaces724 extending from the outer surface 670 to the bone-facing surface 672.A plurality of medial and lateral slots 726 are defined by the planarsurfaces 724 of adjacent ribs 720 and a planar surface 728 of the keel656 that extends between the outer surface 670 and the bone-facingsurface 672. The slots 726 include open ends 730 positioned between thecantilevered ends 722 of the ribs 720. As described in greater detailbelow, the slots 710 cooperate with the slots 726 to define a posteriorchamfer cutting guide 776, a distal cutting guide 784, a posteriorcutting guide 794, an anterior chamfer cutting guide 814, and ananterior cutting guide 842 of the cutting block 652.

Referring now to FIGS. 17-18, the negative contour 674 is formed bynegative contours 740 defined in the flange ribs 700 and beams 704 andnegative contours 750 defined in the medial and lateral ribs 720. Thecontour 740 has a unique set of ridges 742 and depressions 744 that areshaped to engage a corresponding unique set of depressions 106 andridges 108 of an anterior surface 110 of the patient's femur 42 (seeFIG. 22). The contour 750 also has a unique set of ridges 752 anddepressions 754 that are shaped to engage a corresponding unique set ofdepressions 146 and ridges 148 of the condyles 150 of the patient'sfemur 42 and the depressions 126 and ridges 128 of the posterior surface130 of the patient's femur 42. In that way, the cutting block 652 may bepositioned in a unique, pre-planned location on the patient's femur 42.

Referring now to FIG. 19, a medial side 760 of the cutting block 652 isillustrated to show the various medial slots 726 of the cutting block652. It should be noted that a lateral side of the cutting block 652includes the same slots described herein with respect to the medial side760. For example, when a posterior cutting slot is referenced, it shouldbe appreciated that the lateral side of the cutting block 652 alsoincludes a posterior cutting slot that corresponds with the posteriorcutting slot on the medial side 760 of the cutting block 652.

The cutting block 652 includes a rib 770 and a rib 772 that define aslot 774 between their planar surfaces 724. The slot 774 defines aportion of a medial side of the open posterior chamfer cutting guide776. The rib 772 and another rib 780 define a slot 782 between theirplanar surfaces 724, which defines an open portion of a medial side ofthe distal cutting guide 784.

The rib 780 and another rib 790 of the cutting block 652 define anotherslot 792 between their planar surfaces 724, which defines a medial sideof the open posterior cutting guide 794. The posterior cutting guide 794is configured to receive a cutting tool and defines a posteriorresection guide plane 796 extending through the patient's femur 42.

The rib 790 and another rib 800 define a slot 802 between their planarsurfaces 724. The slot 802 is aligned with the slot 774 to define themedial side of the posterior chamfer cutting guide 776. As describedabove, the cutting block 652 includes another pair of slots on itslateral side that defines the lateral side of the posterior chamfercutting guide 776. The posterior chamfer cutting guide 776 is configuredto receive a cutting tool and defines a posterior chamfer resectionguide plane 806 extending through the distal end 40 of the patient'sfemur 42.

The cutting block 652 includes another rib 810, which cooperates withthe rib 800 to define a slot 812 between their planar surfaces 724. Theslot 812 defines an open portion of a medial side of an anterior chamfercutting guide 814.

Referring now to FIG. 20, the rib 810 and ribs 820, 822, 824 cooperateto define a slot 830 between their planar surfaces 724 and 708. The slot830 is aligned with the slot 782 to define a captured end of the distalcutting guide 784. The distal cutting guide 784 is configured to receivea cutting tool and defines a distal resection guide plane 832 extendingthrough the distal end 40 of the patient's femur 42.

The ribs 810, 820, 822, and 824 also cooperate to define a slot 840between their planar surfaces 724 and 708. The slot 840 defines acaptured anterior cutting guide 842 that is configured to receive acutting tool and defines an anterior resection guide plane 844 extendingthrough the patient's femur 42.

The rib 824 and another rib 850 define a slot 852 between their planarsurfaces 708. The slot 852 is aligned with the slot 812 to define acaptured portion of the anterior chamfer cutting guide 814. The anteriorchamfer cutting guide 814 is configured to receive a cutting tool anddefines an anterior chamfer resection guide plane 856 extending throughthe distal end 40 of the patient's femur 42.

Referring now to FIG. 21, the pin guide 680 is configured to receive afixation pin 870 that secures the cutting block 652 to the distal end 40of the patient's femur 42. The pin 870 is positioned in the patient'sintercondylar notch 302, as illustrated in FIG. 22, and is secured tothe surface 304 that defines the intercondylar notch 302. The other pinguide 690 is configured to receive a pin 872 that secures the anteriorflange 654 to the anterior surface 110 of the patient's femur 42.Because the surgeon can resect around the pins 870, 872, the pins 870,872 can remain secured to the bone during the surgical procedure. Insome embodiments, the surgeon may remove the pin 870 when making some ofthe cuts so that the surgeon does not have to resection around the pin870. In such an embodiment, the pin 872 in cooperation with thebone-facing surface 672 holds the cutting block 652 in place on thepatient's femur 42.

In each of the embodiments described above, the surgeon may make theanterior, posterior, posterior chamfer, anterior chamfer, and distalresections with a single cutting block (e.g., cutting blocks 12, 352,652). The cutting block may be attached to the patient's femur in theunique, preplanned location before the first resection is made and mayremain in place until the last resection is made, even as bone materialis removed by the other resections. It should be appreciated that thecutting blocks may have other configurations to achieve a similaroutcome. For example, although the keel is shown positioned at themid-line in the block 352, in other embodiments the keel may be formedalong the medial or lateral side of the block. Additionally, althougheach of the blocks is shown as a single, monolithic component, it shouldbe appreciated that in other embodiments the blocks may be formed frommultiple components that are later assembled. In such embodiments, othermaterials such as, for example, polyethylene may be used to form part ofthe components.

While the disclosure has been illustrated and described in detail in thedrawings and foregoing description, such an illustration and descriptionis to be considered as exemplary and not restrictive in character, itbeing understood that only illustrative embodiments have been shown anddescribed and that all changes and modifications that come within thespirit of the disclosure are desired to be protected.

There are a plurality of advantages of the present disclosure arisingfrom the various features of the method, apparatus, and system describedherein. It should be noted that alternative embodiments of the method,apparatus, and system of the present disclosure may not include all ofthe features described yet still benefit from at least some of theadvantages of such features. Those of ordinary skill in the art mayreadily devise their own implementations of the method, apparatus, andsystem that incorporate one or more of the features of the presentinvention and fall within the spirit and scope of the present disclosureas defined by the appended claims.

The invention claimed is:
 1. An orthopaedic surgical instrumentcomprising: a customized patient-specific 5-in-1 cutting block having aplurality of cutting guides including a first chamfer cutting guide, asecond chamfer cutting guide, an anterior cutting guide, a posteriorcutting guide, and a distal cutting guide, the cutting block comprising:a keel including a distal segment extending from an anterior end to aposterior end, an anterior segment extending proximally from theanterior end of the distal segment, and a posterior segment extendingproximally from the posterior end of the distal segment, a plurality ofribs extending medially and laterally from the distal segment, theanterior segment, and the proximal segment of the keel, each ribincluding a first end coupled to the keel, a cantilevered second end,and a bone-facing surface extending from the first end to the second endof each rib, a pair of pin guides sized to receive bone fixation pins tosecure the cutting block to a patient's femur, wherein both of the pairof pin guides extend through the keel, wherein each bone-facing surfaceof each rib has a customized patient-specific negative contourconfigured to receive a portion of a corresponding positive contour ofthe patient's femur, and wherein the plurality of ribs cooperate todefine the plurality of cutting guides, each cutting guide including aslot having an open outer end defined between corresponding cantileveredsecond ends of adjacent ribs.
 2. The orthopaedic surgical instrument ofclaim 1, wherein each of the first chamfer cutting guide and the secondchamfer cutting guide include medial and lateral slots.
 3. Theorthopaedic surgical instrument of claim 1, wherein: the first chamfercutting guide includes a first slot aligned with a second slot, and thesecond chamfer cutting guide includes a third slot aligned with a fourthslot.
 4. The orthopaedic surgical instrument of claim 1, wherein thedistal cutting guide has medial and lateral slots.
 5. The orthopaedicsurgical instrument of claim 4, wherein the distal cutting guideincludes a first slot aligned with a second slot.
 6. The orthopaedicsurgical instrument of claim 1, wherein each of the anterior cuttingguide and the posterior cutting guide have medial and lateral slots. 7.The orthopaedic surgical instrument of claim 1, wherein the keelincludes a customized patient-specific negative contour configured toreceive a portion of a corresponding positive contour of a surfacedefining a patient's intercondylar notch.